GIT-FSCK(1)                                                Git Manual                                                GIT-FSCK(1)



NAME
       git-fsck - Verifies the connectivity and validity of the objects in the database

SYNOPSIS
       git fsck [--tags] [--root] [--unreachable] [--cache] [--no-reflogs]
                [--[no-]full] [--strict] [--verbose] [--lost-found] [<object>*]


DESCRIPTION
       Verifies the connectivity and validity of the objects in the database.

OPTIONS
       <object>
           An object to treat as the head of an unreachability trace.

           If no objects are given, git fsck defaults to using the index file, all SHA1 references in .git/refs/*, and all
           reflogs (unless --no-reflogs is given) as heads.

       --unreachable
           Print out objects that exist but that aren't readable from any of the reference nodes.

       --root
           Report root nodes.

       --tags
           Report tags.

       --cache
           Consider any object recorded in the index also as a head node for an unreachability trace.

       --no-reflogs
           Do not consider commits that are referenced only by an entry in a reflog to be reachable. This option is meant only
           to search for commits that used to be in a ref, but now aren't, but are still in that corresponding reflog.

       --full
           Check not just objects in GIT_OBJECT_DIRECTORY ($GIT_DIR/objects), but also the ones found in alternate object pools
           listed in GIT_ALTERNATE_OBJECT_DIRECTORIES or $GIT_DIR/objects/info/alternates, and in packed git archives found in
           $GIT_DIR/objects/pack and corresponding pack subdirectories in alternate object pools. This is now default; you can
           turn it off with --no-full.

       --strict
           Enable more strict checking, namely to catch a file mode recorded with g+w bit set, which was created by older
           versions of git. Existing repositories, including the Linux kernel, git itself, and sparse repository have old
           objects that triggers this check, but it is recommended to check new projects with this flag.

       --verbose
           Be chatty.

       --lost-found
           Write dangling objects into .git/lost-found/commit/ or .git/lost-found/other/, depending on type. If the object is a
           blob, the contents are written into the file, rather than its object name.

       It tests SHA1 and general object sanity, and it does full tracking of the resulting reachability and everything else. It
       prints out any corruption it finds (missing or bad objects), and if you use the --unreachable flag it will also print out
       objects that exist but that aren't readable from any of the specified head nodes.

       So for example

           git fsck --unreachable HEAD \
                   $(git for-each-ref --format="%(objectname)" refs/heads)

       will do quite a lot of verification on the tree. There are a few extra validity tests to be added (make sure that tree
       objects are sorted properly etc), but on the whole if git fsck is happy, you do have a valid tree.

       Any corrupt objects you will have to find in backups or other archives (i.e., you can just remove them and do an rsync
       with some other site in the hopes that somebody else has the object you have corrupted).

       Of course, "valid tree" doesn't mean that it wasn't generated by some evil person, and the end result might be crap. git
       is a revision tracking system, not a quality assurance system ;)

EXTRACTED DIAGNOSTICS
       expect dangling commits - potential heads - due to lack of head information
           You haven't specified any nodes as heads so it won't be possible to differentiate between un-parented commits and
           root nodes.

       missing sha1 directory <dir>
           The directory holding the sha1 objects is missing.

       unreachable <type> <object>
           The <type> object <object>, isn't actually referred to directly or indirectly in any of the trees or commits seen.
           This can mean that there's another root node that you're not specifying or that the tree is corrupt. If you haven't
           missed a root node then you might as well delete unreachable nodes since they can't be used.

       missing <type> <object>
           The <type> object <object>, is referred to but isn't present in the database.

       dangling <type> <object>
           The <type> object <object>, is present in the database but never directly used. A dangling commit could be a root
           node.

       sha1 mismatch <object>
           The database has an object who's sha1 doesn't match the database value. This indicates a serious data integrity
           problem.

ENVIRONMENT VARIABLES
       GIT_OBJECT_DIRECTORY
           used to specify the object database root (usually $GIT_DIR/objects)

       GIT_INDEX_FILE
           used to specify the index file of the index

       GIT_ALTERNATE_OBJECT_DIRECTORIES
           used to specify additional object database roots (usually unset)

AUTHOR
       Written by Linus Torvalds <torvaldsATosdl.org[1]>

DOCUMENTATION
       Documentation by David Greaves, Junio C Hamano and the git-list <gitATvger.org[2]>.

GIT
       Part of the git(1) suite

NOTES
        1. torvaldsATosdl.org
           mailto:torvaldsATosdl.org

        2. gitATvger.org
           mailto:gitATvger.org



Git 1.7.4.4                                                04/11/2011                                                GIT-FSCK(1)